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1.
Hypertension ; 74(1): 145-153, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31079531

RESUMO

Preeclampsia is a hypertensive pregnancy disease associated with a massive increase in sFlt-1 (soluble form of the vascular endothelial growth factor 1) in the maternal circulation, responsible for angiogenic imbalance and endothelial dysfunction. Pilot studies suggest that extracorporeal apheresis may reduce circulating sFlt-1 and prolong pregnancy. Nonspecific apheresis systems have potential adverse effects because of the capture of many other molecules. Our concept is based on a specific and competitive apheresis approach using VEGF (vascular endothelial growth factor) functionalized magnetic beads to capture sFlt-1 while releasing endogenous PlGF (placental growth factor) to restore a physiological angiogenic balance. Magnetic beads were functionalized with VEGF to capture sFlt-1. Experiments were performed using PBS, conditioned media from human trophoblastic cells, and human plasma. The proof of concept was validated in dynamic conditions in a microfluidic device as an approach mimicking real apheresis. Magnetic beads were functionalized with VEGF and characterized to evaluate their surface ligand density and recognition capabilities. VEGF-coated magnetic beads proved to be an efficient support in capturing sFlt-1 and releasing PlGF. In static conditions, sFlt-1 concentration decreased by 33±13%, whereas PlGF concentration increased by 27±10%. In dynamic conditions, the performances were improved, with 40% reduction of sFlt-1 and up to 2-fold increase of free PlGF. The sFlt-1/PlGF ratio was reduced by 63% in the plasma of preeclamptic patients. Apheresis was also associated with VEGF release. A ligand-based approach using VEGF-coated beads is an effective approach to the capture of sFlt-1 and the release of endogenous PlGF. It offers new perspectives for the treatment of preeclampsia.


Assuntos
Dispositivos Lab-On-A-Chip , Pré-Eclâmpsia/terapia , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Indutores da Angiogênese , Remoção de Componentes Sanguíneos/métodos , Velocidade do Fluxo Sanguíneo , Células Cultivadas , Feminino , Humanos , Técnicas In Vitro , Magnetismo/métodos , Projetos Piloto , Placenta/citologia , Pré-Eclâmpsia/patologia , Gravidez , Sensibilidade e Especificidade , Trofoblastos/citologia , Trofoblastos/fisiologia
2.
Bioconjug Chem ; 29(8): 2646-2653, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-29989798

RESUMO

The use of functionalized magnetic particles is increasing because they simplify the analytical process and yield promising results in a wide range of applications. Particularly, streptavidin-coated magnetic beads offer the possibility of rapid and very efficient grafting of biomolecules. Unfortunately, current methods to monitor and compute this grafting process are cumbersome and scarce. We describe herein a simple, rapid, and reliable chemiluminescent assay we have developed to check the grafting rate of functionalized magnetic beads. The power of the assay also relies on its ability to predict the amount of ligands required to obtain a precise grafting rate. In addition, results were correlated with a more general parameter in material functionalization characterization like surface ligand density. Finally, the assay was validated for a wide variety of biotinylated biomolecule sizes, ranging from small molecules (around 200 Da) to antibodies (around 150 kDa). This approach will allow a precise quantification and prediction of the functionalization of magnetic particles that is of enormous importance for quality control in many applications.


Assuntos
Medições Luminescentes/normas , Magnetismo , Proteínas/química , Estreptavidina/química , Bioensaio , Biotinilação , Peroxidase do Rábano Silvestre/química , Ligantes , Peso Molecular , Propriedades de Superfície
3.
PLoS One ; 12(12): e0189385, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29261724

RESUMO

BACKGROUND: To describe a large cohort of women with non-puerperal inflammatory breast and to identify characteristics of inflammatory breast cancer. METHODS: All patients consulting for inflammatory breast syndrome in the breast unit of our tertiary University hospital between September 2013 and December 2015 were prospectively included. We excluded women who were pregnant or in the postpartum period. Patients underwent systematic clinical examination and imaging (breast ultrasonography and mammography). A biopsy was performed if the clinician suspected a malignant lesion of the breast. Clinicopathologic and radiologic data were registered. Statistics were performed using R (3.0.2 version) software. RESULTS: Among the 76 patients screened and included, 38 (50%) had a malignant lesion at final diagnosis, 21 (27.6%) were diagnosed with infectious disease and 17 (22.4%) with inflammatory disease of the breast. When compared to patients with benign disease, patients with a malignant lesion were significantly older (p = 0.022, CI95% 1.78-14.7), had a significantly bigger palpable mass (p<0.001, CI 95% 22.8-58.9), were more likely to have skin thickening (p = 0.05) and had more suspicious lymph nodes at clinical examination (p<0.001, CI 95% 2.72-65.3). Precise limits on ultrasonography were significantly associated with benign lesions. The presence of a mass (p = 0.04), micro calcifications (p = 0.04) or of focal asymmetry (p<0.001, CI95% 1.3-618) on mammography was significantly associated with malignant disease. CONCLUSION: Inflammatory breast cancer was common in our cohort of women consulting for inflammatory breast syndrome. Identifying these patients with high-risk malignancy is crucial in the management of an inflammatory breast.


Assuntos
Neoplasias Inflamatórias Mamárias/epidemiologia , Adulto , Feminino , Humanos , Incidência , Neoplasias Inflamatórias Mamárias/diagnóstico por imagem , Neoplasias Inflamatórias Mamárias/patologia , Imageamento por Ressonância Magnética , Mamografia , Pessoa de Meia-Idade , Ultrassonografia Mamária/métodos
4.
Artigo em Inglês | MEDLINE | ID: mdl-26253238

RESUMO

Second-line methods of foetal monitoring have been developed in an attempt to reduce unnecessary interventions due to continuous cardiotocography (CTG), and to better identify foetuses that are at risk of intrapartum asphyxia. Very few studies directly compared CTG with foetal scalp blood (FBS) and CTG only. Only one randomised controlled trial (RCT) was published in the 1970s and had limited power to assess neonatal outcome. Direct and indirect comparisons conclude that FBS could reduce the number of caesarean deliveries associated with the use of continuous CTG. The main drawbacks of FBS are its invasive and discontinuous nature and the need for a sufficient volume of foetal blood for analysis, especially for pH measurement, resulting in failure rates reaching 10%. FBS for lactate measurement became popular with the design of test-strip devices, requiring <0.5 mL of foetal blood. RCTs showed similar outcomes with the use of FBS for lactates compared with pH in terms of obstetrical interventions and neonatal outcomes. In conclusion, there is some evidence that FBS reduces the need for operative deliveries. However, the evidence is limited with regard to actual standards, and large RCTs, directly comparing CTG only with CTG with FBS, are still needed.


Assuntos
Acidose/diagnóstico , Asfixia Neonatal/diagnóstico , Sangue Fetal/química , Hipóxia Fetal/diagnóstico , Ácido Láctico/sangue , Acidose/sangue , Asfixia Neonatal/sangue , Coleta de Amostras Sanguíneas/métodos , Paralisia Cerebral , Feminino , Hipóxia Fetal/sangue , Monitorização Fetal/métodos , Humanos , Concentração de Íons de Hidrogênio , Recém-Nascido , Trabalho de Parto , Gravidez , Couro Cabeludo
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